When a bus line pattern or the like is formed by ink jet method, it is necessary to increase wettability of interface of a glass substrate and to eliminate defects (such as disconnection, short-circuiting, etc.) caused by incomplete wetting and expansion or variation in distribution of the ink. As a method to eliminate such defects, emphasis is now put on the improvement of the surface quality. In particular, in case of a glass substrate with larger area, it is difficult to maintain stable surface conditions because it is not very easy to remove the residues caused by dry etching or to perform lyophilic processing and also to have adequate lyophilic processing conditions by wet etching. In this respect, it is very difficult to maintain stable surface conditions and to have successful liquid process, and there are also many problems to be solved.
JP-A-2003-273097 discloses a method for forming a bus line pattern by coating a coating material solution by ink jet method on the surface of a substrate with micro-size depressions or surface irregularities. In this reference, a pattern forming method is described. Specifically, lyophobic processing is performed on a portion except the patterned portion, and lyophilic processing is performed on a patterned portion. A solution of coating material in mist condition is dispersed on the surface of the substrate, and the coating material solution is filled into micro-size depressions. Further, the coating material is coated on the substrate surface, and the coating material solution is filled into the micro-size depressions.
[Patented Reference 1] JP-A-2003-273097